Figure SPM.6.a. Warming in two IPCC scenarios reveals humanity’s choice. With aggressive action to reduce greenhouse gas emissions (RCP 2.6 with 443 ppm of CO2 in 2100), warming is modest and adaptation is plausible. With continued inaction (RCP 8.5 with 936 ppm in 2100), warming is a catastrophic and unmanageable 10°F over much of Earth’s habited and arable land — and more than 15°F over the Arctic. This projection ignores many key amplifying feedbacks, such as the release of permafrost carbon, which would likely lead to far greater warming.

The draft 2013 Fifth Assessment report of the Intergovernmental Panel on Climate Change leaked this week makes clear inaction on climate change would be devastating to modern civilization. The report finds that the human fingerprint on climate has grown more obvious, concluding “it is virtually certain” the energy imbalance that causes global warming “is caused by human activities, primarily by the increase in CO2 concentrations. There is very high confidence that natural forcing contributes only a small fraction to this imbalance.”

Yes, I know, the easily-duped deniers and their media stooges have reported the opposite is true, that solar forcing has been a significant driver of recent warming, but the deniers are as likely to be right as the flat earthers. The only question is why anyone still listens to them. I’ll repost a debunking of their nonsense below.

It is extremely likely [“>95% probability”] that human activities have caused more than half of the observed increase in global average surface temperature since the 1950s. There is high confidence [“About 8 out of 10 chance“] that this has caused large-scale changes in the ocean, in the cryosphere, and in sea level in the second half of the 20th century. Some extreme events have changed as a result of anthropogenic influence.

For me, the leaked draft, which has not yet been peer reviewed — and thus still has time to be watered down yet more — underscores how pointless the IPCC has become. Like the 4th assessment before it, this ultra-conservative and instantly obsolete report ignores the latest science — see “Fifth Assessment Report Will Ignore Crucial Permafrost Carbon Feedback!” Note that including the permafrost feedback would probably make the RCP8.5 scenario in the top figure as much as 1.5°F warmer!

And like the AR4, the AR5 scenarios low-ball future impacts — “Arctic sea ice area is projected to decrease by 28% for September” for the 2016–2035 period vs. 1986–2005. Seriously IPCC, a 28% drop is the scenario your touting? In fact, as we have reported, many experts warn of “Near Ice-Free Arctic In Summer” in a decade if recent ice volume trends continue.

Even so, the uber-conservative AR5 draft makes clear to anyone who reads between the lines that inaction would be suicidal for humanity, with devastating warming and sea level rise that could hit a half a foot a decade by 2100. How precisely does one adapt to that?

Indeed, the report guts the one remaining myth of those who downplay future impacts, that clouds would act as a negative (or weakening) feedback. It finds:

In it most extreme scenario, RCP8.5 — about 936 ppm of CO2 in 2100 (not a worst-case in the real world because of permafrost and other feedbacks) — sea level rise in 2100 is only about 2 feet. That assumes you can figure out what this means: “The contributions from ice sheet dynamical change and anthropogenic land water storage are treated as independent of scenario, since scenario dependence cannot be evaluated on the basis of existing literature, and as having uniform probability distributions, uncorrelated with the magnitude of global climate change.” Clarity ain’t the IPCC’s strong suit.

Finally, if you read the denier blogs or columnists — and if so, you have no one to blame but yourself — you’ve probably heard something about how the IPCC finds cosmic rays are a major climate driver. In fact, the SPM finds:

Cosmic rays enhance aerosol nucleation and cloud condensation nuclei production in the free troposphere, but there is high confidence that the effect is too weak to have any significant climatic influence during a solar cycle or over the last century.

For debunkings of the latest denier spin, see here and here and especially here, which has an interview with the lead author of the key draft chapter.

If the IPCC was to report that the sun is a significant player in the current rapid global warming, that would indeed be major news, because the body of peer-reviewed scientific literature and data clearly show that the sun has made little if any contribution to the observed global warming over the past 50+ years (Figure 1).

So why would the latest IPCC report contradict these studies when its purpose is to summarize the latest and greatest scientific research? The answer is simple — it doesn’t. Rawls has completely misrepresented the IPCC report.

Cosmic Source of Confusion

The supposedly “game-changing admission” from the IPCC report is this:

“Many empirical relationships have been reported between GCR [galactic cosmic rays] or cosmogenic isotope archives and some aspects of the climate system…The forcing from changes in total solar irradiance alone does not seem to account for these observations, implying the existence of an amplifying mechanism such as the hypothesized GCR-cloud link.”

This statement refers to a hypothesis of Henrik Svensmark from the Danish National Space Institute, who has proposed that galactic cosmic rays (GCRs) could exert significant influence over global temperatures. The GCR hypothesis suggests that when they reach Earth, GCRs (high-energy charged particles originating from somewhere in our galaxy) are capable of “seeding” clouds; thus at times when a lot of GCRs are reaching the Earth’s surface, more clouds will form. Clouds generally have a cooling effect on the Earth’s temperature, because they reflect sunlight.

So the hypothesis goes like this: high solar activity means a strong solar magnetic field, which deflects more GCRs away from Earth, which means less cloud formation, which means less sunlight is reflected away from Earth, which means more warming. This GCR-caused warming would amplify the warming already being caused by increased solar activity. Conversely, cooling from decreased solar activity would hypothetically be amplified by more GCRs on Earth, more clouds, more reflected sunlight, and thus more cooling.

“…there is medium evidence and high agreement that the cosmic ray-ionization mechanism is too weak to influence global concentrations of [cloud condensation nuclei] or their change over the last century or during a solar cycle in any climatically significant way.”

But more importantly in this context, even if GCRs did influence global temperature, they would currently be having a cooling effect.

Solar Activity is Down, Greenhouse Gases are Up

Rawls also provides the following quote from the IPCC report (emphasis added):

“There is very high confidence that natural forcing is a small fraction of the anthropogenic forcing. In particular, over the past three decades (since 1980), robust evidence from satellite observations of the TSI [total solar irradiance] and volcanic aerosols demonstrate a near-zero (–0.04 W m–2) change in the natural forcing compared to the anthropogenic AF increase of ~1.0 ± 0.3 W m–2.”

The term “radiative forcing” refers to a global energy imbalance on Earth, which may be caused by various effects like changes in the greenhouse effect or solar activity. A positive forcing will result in warming temperatures, while a negative forcing will result in cooling.

Here the IPCC is saying that since 1980, the sun and volcanoes have combined to cause a slightly negative global energy imbalance, which means they have had a slight cooling influence on global temperatures over the past three decades. Indeed, solar activity has decreased a bit over that timeframe (Figure 2).

As we would expect, lower solar activity including a weaker solar magnetic field has translated into a slight increase in GCR flux on Earth (Figure 3). Note that on the left-hand axis of Figure 3, GCR counts decrease going up the axis in order to show the relationship with temperature, since fewer GCRs hypothetically means fewer clouds, less reflected sunlight, and higher temperatures.

Physical Reality Intrudes on Rawls

Rawls has argued to the contrary by claiming that the climate is still responding to the increase in solar activity from the early 20th century, and that GCRs are amplifying that solar warming from over 60 years ago. This argument is simply physically wrong. As Figure 2 illustrates, when solar activity rises, temperatures follow suit very soon thereafter. In fact, during the mid-20th century, solar activity and global surface temperatures both flattened out. Are we to believe that the planet suddenly began responding to the pre-1950 solar activity increase in 1975—2012, after not warming 1940—1975? The argument makes no physical sense.

On top of that, the hypothetical GCR process is a relatively rapid one. Cloud formation from GCR seeding should occur within days, and clouds have very short lifetimes. For GCRs to have a warming effect, solar activity must be increasing right now. It is not, in fact solar activity has been essentially flat and slightly declining in recent decades. Changes in solar activity from 60+ years ago have no bearing whatsoever on GCRs today.

IPCC Shows Global Warming is NOT Solar

To sum up,

The leaked IPCC report states that there may be some connection between GCRs and some aspects of the climate system.

However, the report is also consistent with the body of scientific literature in stating that research indicates GCRs are not effective at seeding clouds and have very little influence on global temperatures.

Solar activity has been nearly flat and slightly decreasing in recent decades, meaning that if GCRs do amplify solar influences on climate, they are amplifying a cooling effect.

The body of peer-reviewed scientific literature is very clear: human greenhouse gas emissions, not solar activity or galactic cosmic rays, are causing global warming. The leaked IPCC report is entirely consistent with this conclusion. In fact, in attempting to argue to the contrary, Rawls has scored an own goal by showing that if anything, GCRs are currently amplifying a solar cooling effect.

“It is very likely that the Arctic sea ice cover will continue to shrink and thin in the course of the 21st century as global temperature rises.”

Yes, but what does this mean for the planet’s energy balance?

The amplifying feedback mechanism of polar ice melt is the so-called albedo-flip effect, where loss of reflection by melted ice is compounded by infrared absorption by open water, a process currently taking place in the Arctic Sea, as reported by Hansen et al.: “… amplifying feedbacks make ice sheet disintegration necessarily highly non-linear. In a non-linear problem, the most relevant number for projecting sea level rise is the doubling time for the rate of mass loss. Hansen (2007) suggested that a 10-year doubling time was plausible, pointing out that such a doubling time from a base of 1 mm per year ice sheet contribution to sea level in the decade 2005-2015 would lead to a cumulative 5 m sea level rise by 2095.” http://www.countercurrents.org/glikson050411.pdf

He’s not still on about his mysterious stored solar energy stuck at the bottom of the sea, is he? Got stuck into him on his own blog about this several months ago (with a little bit of much appreciated help from Mike Lockwood) – he thought sunspot cycles were warming the sea and we hadn’t noticed because the heat transfer was all happening at the 700m boundary. Apparently it hadn’t occurred to him that a cyclical temperature change such as sunspot activity would have its signal damped at a boundary where conductance and convection were poor, and the net would be no change. The earth is this big homogenous piece of tinfoil, you know, all heats up and cools down simultaneously and is in permanent thermal equilibrium….. :(

“Arctic sea ice area is projected to decrease by 28% for September” for the 2016–2035 period vs. 1986–2005.”

This is such an amazing understatement! Let’s look at the already existing data. During 1986-2005 the September sea-ice extent was mostly from six to seven and half million square kilometers. 2012 was 3.6 million square kilometers. That’s 35 percent below the lowest year of the 1986-2005, 2005 which was 5.6 million square kilometers. So 2012 must have been much more than 35 percent below the 1986-2005 average. (It would be nice if someone quickly calculated this average.)

IPCC is clearly saying that they predict the September sea-ice extent to increase in 2016-2035 from current levels. Of course we all hope that would happen, but for it to happen, huge action is necessary. HUGE!

In a business-as-usual scenario the sea-ice simply don’t grow from now to 2016-2035. Period.

Yes, and this means Global Emergency! Immediate action is necessary to cool the Arctic and protect the sea ice. 100% (or 95% or whatever is the absolute maximum possible) emissions cuts and improving the sinks is not enough, because it still takes so long before cooling starts. (According to James Hansen’s estimate, when CO2 is at 345 ppm and methane and black soot emissions have been cut also.)

“Sunspot number: 35 … Updated 09 Dec 2012” (“What’s up in Space”; Dr. Tony Phillips; spaceweather.com, 12/9/12). “Sunspot number: 71 … Updated 13 Dec 2012” (“What’s up in Space”; Dr. Tony Phillips; spaceweather.com, 12/15/12). “SDF Number 343 Issued at 2200Z on 08 Dec 2012 … IA. Analysis of Solar Active Regions and Activity from 07/2100Z to 08/2100Z: Solar activity has been at low levels for the past 24 hours. … here are currently 3 numbered sunspot regions on the disk” (“Joint USAF/NOAA Report of Solar and Geophysical Activity Report and Forecast”; Prepared jointly by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center and the U.S. Air Force; swpc.noaa.gov/forecast.html, 8 December 2012).
“SDF Number 350 Issued at 2200Z on 15 Dec 2012 … IA. Analysis of Solar Active Regions and Activity from 14/2100Z to 15/2100Z: … There are currently 5 numbered sunspot regions on the disk” (“Joint USAF/NOAA Report of Solar and Geophysical Activity Report and Forecast”; Prepared jointly by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center and the U.S. Air Force; swpc.noaa.gov/forecast.html, 15 December 2012).

Deniers can predict only a free lunch. “Our current solar cycle 24 – still in a slump – solar max reached? … Posted on December 10, 2012 by Anthony Watts … topped out for solar cycle 24 … doesn’t seem to be any evidence of resurgence … a generally quiet magnetic period … 11 Responses to Our current solar cycle 24 – still in a slump – solar max reached? … Olavi says: December 10, 2012 at 11:13 am … Very soon Climate Scientists find out that is’s the Sun STUPID…. lsvalgaard says: December 10, 2012 at 11:24 am … REPLY: … There’s some software that I can run … Anthony… vukcevic says: December 10, 2012 at 11:50 am … Very soon Climate Scientists find out that is’s the Sun STUPID” (Tony ‘who lacked a mothers’ love because she preferred suckling a pack of cleaner cigarettes’ Watts; whistlesuckers perfuming the stink at wattsupwiththat.com).

Not a helpful report to get the action we need. As we here well know any little bit of soft pedaling is very dangerous. We are not meeting the challenge of this global crisis,any little excuse to delay drops the changes of our societal survival. At this point stright talk and up to date information are what the global community needs. Nothing short of that is going get the action we need. For ourselves and our children.

I greatly appreciate Joe’s blunt honesty on this score. Something appears to have gone terribly wrong with the IPCC, as its process and product get ever more tortuously equivocal. This is a tragedy for science, and for the world. As international consensus and action is absolutely critical for any effective approach to AGW, the failures of the IPCC could not possibly be more devastatingly consequential.

Is this by design, or just institutional inertia? Is there any way to get the IPCC back on the track of relevancy? The world vitally needs a responsible IPCC.

You’re right, Solar Jim, but IPCC is now entrenched. I met scientists at AGU who were clearly flattered to be authors of V. Governments like it because IPCC ignores events until they have happened (such as permafrost methane leakage).

IPCC needs a rival that will render it timid and irrelevant. Scientific academies from the G22 could form such a group, and issue reports that are contemporary, accurate, and direct. Pielke Jr. and the Saudi Arabia Minister of Energy would not have review input.

JR:
“No, really, it is “very likely” — “> 90% probability” — which I guess means, what, that the IPCC seriously thinks there is an up to 10% chance Arctic sea ice cover will stop shrinking and thinning???”

Actually, there is “> 90% probability” that Artic sea ice will be *gone* before AR5 is even published.

Is this all the deniers have now? A touted “game changer” that they got totally backwards. Heck, even the godfather of the GCR-climate theory has been remarkably quiet after 2010 was the warmest on record right at the lowest solar slump in a century. Mother Nature herself not only thoroughly disproved, but actually stomped on the claim that GCRs have major impact on climate. Instead of keeping quiet about that spectacular failure, the deniers now feel the need to remind us about it. They can’t be all that bright.

Yep, I can remember we laughed about it in the 1970s because we knew the world would act to stop it – that was when cooperation was taken for granted because people actually did work together. Yeah, I know I come from the past, ME

As the emissions scenarios considered here illustrate, even well-intentioned and effective international efforts to limit climate change must face the hard physical reality of certain temperature targets that can no longer be achieved if too much carbon has already been emitted to the atmosphere. “Both delay and insufficient mitigation efforts close the door on limiting global mean warming permanently. This constitutes more than a climate change commitment: It is the fast and irreversible shrinking, and eventual disappearance, of the mitigation options with every year of increasing greenhouse gas emissions.”

Food, food, food. It’s all about food. Let’s stop focusing on sea level rise, and start explaining to the masses that we’ve evolved into an agricultural species, and that agriculture depends on a stable climate. Our food systems and food security are what’s at stake.

Losing the “air conditioning” effect of the Arctic summer sea ice is going to devastate the northern hemisphere’s grain belts. And then where is that latent heat going to go?

What it could mean is a permanent shift in the behavior of the jet stream and the associated seasonal highs and lows that agriculture depends on. In other words, the disappearance of the ice cap could mean the total systemic failure of the atmosphere from the POV of ag.

The deniers should have the burden to put forward an alternative to the anthropogenic GHG theory. Saying it could be something else shouldn’t be allowed to pass. Show us what it is, then.

Otherwise, they’re just children trying to deflect the conversation away from something they don’t want to be true, like six-year-olds who, standing among broken glass, say they didn’t do it because they don’t want to deal with the consequences of admitting the truth.

Like everyone else, I couldn’t believe they “forecast” a 28% drop in Arctic Ice area from the 1986-2005 period. Where the hell have they been? Using Cryosphere Today (U of Illinois) data, I calculate the average arctic ice area for 2007-12 (inclusive) was 36.6% below the 1986-2005 average. Do they seriously believe the ice is going to increase over the average of the last six years?